Pneumatic product-on-demand delivery systems have been used on agricultural seeding machines to automatically direct seed from a main seed hopper to a plurality of individual planting units. Each of the individual planting units has an auxiliary seed hopper for receiving the seed, a seed meter for metering the seed from the auxiliary seed hopper and a furrow opener for forming a planting furrow into which the metered seed is deposited. A fan is used to create pressurized air that forms an air stream on which the seed is taken to the planting units. These systems automatically replenish the auxiliary hoppers as needed. An example of a pneumatic product-on-demand delivery system is shown in U.S. Pat. No. 7,025,010.
A pneumatic product-on-demand delivery system has a series of hoses to deliver the seed from the main seed hopper to the auxiliary seed hopper. The product hose has a connection point that allows the hose to be disconnected from the hopper for the meter to be removed. If this connection works its way off while planting, then the delivery system will keep running and spread seed on the ground. This will likely not be noticed until the operator turns around at the end of the row to plant in the other direction. By that time, the system has dropped several bushels of expensive seed onto the ground which can no longer be used.